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Abstract:

A device for clamping tissue includes a first jaw having a distal portion
for communicating with tissue and a proximal portion having a first wing
and a second wing. The device also includes a second jaw having a distal
portion for communicating with tissue and a proximal portion having a
first slot and a second slot, the first slot disposed between a middle
structure and a first lateral structure, the second slot disposed between
the middle structure and a second lateral structure. The first jaw is
rotatably coupleable to the second jaw with the first wing extending into
the first slot and the second wing extending into the second slot.

Claims:

1. A device for clamping tissue, comprising: a first jaw including: a
distal portion adapted to communicate with tissue, and a proximal portion
having a first wing and a second wing; and a second jaw including: a
distal portion adapted to communicate with tissue, and a proximal portion
having a first slot and a second slot, the first slot disposed between a
middle structure and a first lateral structure, the second slot disposed
between the middle structure and a second lateral structure, wherein the
first jaw is rotatably coupleable to the second jaw with the first wing
extending into the first slot and the second wing extending into the
second slot.

2. The device of claim 1, wherein the first wing includes a first blind
slot and the second wing includes a second blind slot, the first and
second blind slots configured to receive opposite ends of an actuation
shaft.

3. The device of claim 2, wherein the middle structure of the second jaw
includes a slot configured to receive a middle portion of the actuation
shaft when the ends of the actuation shaft are received in the blind
slots of the first and second wings.

4. The device of claim 1, wherein the first jaw includes a first bearing
surface formed monolithically with the first jaw and the second jaw
includes a second bearing surface formed monolithically with the second
jaw, the first bearing surface communicating with the second bearing
surface to define an axis of rotation between the first jaw and the
second jaw when the first jaw is rotatably coupled to the second jaw.

5. The device of claim 4, wherein the first and second bearing surfaces
have curvatures that maintain an axial position of the first jaw with
respect to the second jaw when a clamping force is applied between the
first jaw and the second jaw.

6. The device of claim 4, further comprising a secondary positioning
member coupled to one of the first jaw and the second jaw and configured
to prevent removal of the first jaw from the second jaw and to allow
rotation of the first jaw with respect to the second jaw.

7. The device of claim 6, wherein the secondary positioning member is at
least one of a pin and a screw.

8. The device of claim 6, wherein the secondary positioning member is
configured to extend from the one of the first jaw and the second jaw
into a curved slot of the other one of the first jaw and the second jaw.

9. The device of claim 8, wherein the curved slot is a blind slot.

10. The device of claim 1, wherein the first jaw is an anvil and the
second jaw is a staple cartridge housing configured to drive staples into
the anvil when the anvil is in a closed position.

11. A device for clamping tissue, comprising: a first jaw including: a
first jaw body having a proximal portion and a distal clamping portion,
and a first bearing surface formed monolithically with the first jaw body
as a single piece; a second jaw including: a second jaw body having a
proximal portion and a distal clamping portion, and a second bearing
surface formed monolithically with the second jaw body, the second jaw
being rotatably coupleable to the first jaw such that the first bearing
surface communicates with the second bearing surface at an interface; and
a driver configured to rotate the first jaw with respect to the second
jaw with the interface acting as a fulcrum and defining an axis of
rotation between the first jaw and the second jaw.

12. The device of claim 11, wherein the first bearing surface and the
second bearing surface are configured to slide with respect to each other
along the interface when the driver rotates the first jaw with respect to
the second jaw.

13. The device of claim 12, wherein the interface extends along a
circular arc, the first jaw rotatable with respect to the second jaw
about an axis of rotation corresponding to the circle center of the
circular arc.

14. The device of claim 11, wherein the first bearing surface is formed
in the first jaw without extending entirely through the first jaw and the
second bearing surface is formed in the second jaw without extending
entirely through the second jaw.

15. The device of claim 11, wherein the first jaw includes a first wing
and a second wing, the first wing including a first blind slot and the
second wing including a second blind slot.

16. The device of claim 15, wherein the driver includes a shaft
configured to extend into each of the first blind slot and the second
blind slot.

17. The device of claim 16, wherein the shaft is actuatable along a slot
in the second jaw to rotate the first jaw with respect to the second jaw.

18. The device of claim 17, wherein the shaft is disposed proximally with
respect to the interface between the first bearing surface and the second
bearing surface.

19. The device of claim 10, wherein the first jaw is axially insertable
and removable from the second jaw when no clamping force is applied
between the first jaw and the second jaw.

20. The device of claim 19, further comprising a secondary positioning
member coupled to one of the first jaw and the second jaw and configured
to prevent axial removal of the first jaw from the second jaw and to
permit rotation of the first jaw with respect to the second jaw.

21. The device of claim 20, wherein the secondary positioning member is
configured to limit the range of rotation between the first jaw and the
second jaw to a predetermined angular range.

22. The device of claim 20, wherein the secondary positioning member is
configured to extend from the one of the first jaw and the second jaw
into a curved slot of the other one of the first jaw and the second jaw.

23. The device of claim 22, wherein the curved slot is a blind slot.

Description:

[0002] Some surgical procedures require the compression, e.g., clamping,
of a patient's tissue. Such procedures may include, e.g., anastomosing,
stapling, and resecting of tissue. For example, where cancerous tissue is
identified in a patient's gastrointestinal tract, the cancerous tissue
may need to be surgically removed. Where, for example, the cancerous
tissue is located on the colon and is accessible by surgical
instrumentation, the surgeon may make an incision in the patient's
abdomen to allow access to the bowel. The surgeon may then use a linear
cutting and stapling device, such as that described in U.S. Patent
Application Publication No. 2009/0101692, which is expressly incorporated
herein in its entirety by reference thereto, to cut and staple the colon
tissue on opposite sides of the cancerous portion to be removed. In this
procedure, the colon is externally clamped (e.g., between opposed jaws)
to compress the tissue. While the tissue is compressed, a cutter and a
stapler are activated to make a linear cut and apply typically two linear
rows of staples in the areas adjacent the cut.

[0003] The stapling thus closes both open ends of the portion of the bowel
to be removed, as well as providing a temporary closure of the two cut
ends of the bowel. This closure limits exposure of the surrounding tissue
to the interior of the bowel, thus limiting the risk of infection.

[0004] After the cutting and stapling procedure, the cancerous portion of
tissue may be removed from the patient's body.

[0005] To achieve effective stapling, e.g., in the above procedures, the
tissue must be compressed to the extent that there is an adequately small
tissue gap, e.g., one millimeter, between the faces of the tool. During
this compression, the mechanical components of the clamping mechanism of
the cutting and stapling device may be subjected to a high level of force
or strain. Where, e.g., the jaws are closed by rotation of one or both of
the jaws about a proximally located pin, the pin and/or the adjacent
structures of the jaws in communication with the pin bear a substantial
load, which may lead to deformation. Where the pin passes through a
through hole in one or both of the jaws, deformation may be more likely
due to the weakening of the jaw structure resulting from the through
holes.

[0006] Further, proximally extending structures of the jaws, e.g., an
anvil, may deform, including, e.g., splaying laterally outwardly. The
likelihood of deformation may also be increased by the removal of
material for through slots, e.g., in a pin-and-slot type actuation
arrangement.

[0007] This deformation may lead to, e.g., misalignment between the jaws
and/or failure of the clamping mechanism. Where one of the jaws is
configured as an anvil and the other jaw is configured to drive staples,
e.g., from a staple cartridge, into the anvil, misalignment of the jaws
may cause misalignment of the anvil and staple pockets. This may cause
the staples to be improperly formed, which may increase the risk of
sepsis and other potentially dangerous complications.

[0008] Thus, it is desirable to provide a clamping mechanism that
substantially reduces the likelihood of deformation in the jaws.

SUMMARY

[0009] Example embodiments of the present invention provide a
high-strength anvil and housing while maintaining accurate anvil to
staple pocket positioning. This may be accomplished by integrating the
pivot point into the anvil and housing geometry rather than using a
separate pivot pin. This design may be advantageous in that the integrity
of the anvil and housing is not compromised by the need to drill a
through hole for a pin. In this regard, a portion of material (which
would otherwise be removed due to drilling of a through hole) remains in
the region of the pivot point to assist in supporting the significant
loads exerted during the compression of tissue. This may result in
increased clamping force with less deflection in the anvil and/or the
housing.

[0010] Accurate distal to proximal anvil positioning may be accomplished
by providing the anvil and cartridge housing with mating geometry, e.g.,
mating cylindrical surfaces. For example, the anvil or the cartridge
housing may have a concave cylindrical surface that receives a convex
cylindrical surface (which may have the same, or substantially the same,
radius of curvature) of the other of the anvil or the cartridge housing.
It should be understood that the device may have multiple mating
interfaces and that one of the anvil and the cartridge housing may have a
combination of convex and concave geometries that mate with a
corresponding combination of concave and convex geometries on the other
of the anvil and the cartridge housing.

[0011] When the mating surfaces of the anvil and the cartridge housing are
mated and clamping force is exerted between the anvil and the cartridge
housing, the mated surfaces of the anvil and the cartridge housing
accurately locate, or position, the anvil. In this regard, the example
device is configured such that applying a load to the anvil during
clamping causes the mating surfaces to be pressed toward each other,
thereby maintaining the mated arrangement. In the absence of a load being
applied to the anvil, or when the mated surfaces are not being pressed
together, the position of the anvil is maintained by a secondary
positioning member, e.g., a secondary pin or screw, which may, e.g., be
supported by the housing and received by the anvil, e.g., in a slot of a
wing of the anvil. Where the secondary positioning member is received in
a slot, the slot may be a blind slot as opposed to a through slot, to
avoid potential weakening of the structure. It should be appreciated that
the secondary positioning member may be supported in either of the anvil
and the cartridge housing. Further, a plurality of secondary positioning
members may be provided such that either or both of the anvil and the
cartridge housing support the positioning members.

[0012] According to an example embodiment, the anvil and cartridge housing
are configured so that the anvil is generally laterally confined in a
particular arrangement by the cartridge housing. This is accomplished by
one or more structures of the anvil being receivable in a slot or space
formed in the cartridge housing. For example, two wings of the anvil may
be received in two corresponding slots of the cartridge housing. This
slot configuration allows the presence of the cartridge housing structure
around a relatively high portion of the circumference of the cartridge
housing, which may be advantageous with regard to the strength of the
cartridge housing.

[0013] The slotted arrangement may also be advantageous with regard to the
anvil, since the structure of the cartridge housing extends on laterally
outward sides of the wings and between the wings when the anvil is mated
to the cartridge housing. This may, e.g., decrease the likelihood of
lateral deflection of the wings.

[0014] The anvil of the example embodiment also has a cam slot for
actuation of the anvil that does not extend laterally through the anvil.
This blind slot may increase the strength of the anvil due to the
presence of more structure on the outer surface as opposed to a through
slot.

[0015] According to an example embodiment of the present invention, a
device for clamping tissue includes a first jaw having a distal portion
for communicating with tissue and a proximal portion having a first wing
and a second wing. The device also includes a second jaw having a distal
portion for communicating with tissue and a proximal portion having a
first slot and a second slot, the first slot disposed between a middle
structure and a first lateral structure, the second slot disposed between
the middle structure and a second lateral structure. The first jaw is
rotatably coupleable to the second jaw with the first wing extending into
the first slot and the second wing extending into the second slot.

[0016] The first wing may include a first blind slot and the second wing
may include a second blind slot, the first and second blind slots
configured to receive opposite ends of an actuation shaft.

[0017] The middle structure of the second jaw may include a slot
configured to receive a middle portion of the actuation shaft when the
ends of the actuation shaft are received in the blind slots of the first
and second wings.

[0018] The first jaw may include a first bearing surface formed
monolithically with the first jaw and the second jaw may include a second
bearing surface formed monolithically with the second jaw, the first
bearing surface communicating with the second bearing surface to define
an axis of rotation between the first jaw and the second jaw when the
first jaw is rotatably coupled to the second jaw.

[0019] The first and second bearing surfaces may have curvatures that
maintain an axial position of the first jaw with respect to the second
jaw when a clamping force is applied between the first jaw and the second
jaw.

[0020] The device may also include a secondary positioning member coupled
to one of the first jaw and the second jaw and configured to prevent
removal of the first jaw from the second jaw and to allow rotation of the
first jaw with respect to the second jaw.

[0021] The secondary positioning member may be at least one of a pin and a
screw.

[0022] The secondary positioning member may be configured to extend from
the one of the first jaw and the second jaw into a curved slot of the
other one of the first jaw and the second jaw.

[0023] The curved slot may be a blind slot.

[0024] The first jaw may be an anvil and the second jaw may be a staple
cartridge housing configured to drive staples into the anvil when the
anvil is in a closed position.

[0025] According to an example embodiment of the present invention, a
device for clamping tissue includes a first jaw having a first jaw body
having a proximal portion and a distal clamping portion, and a first
bearing surface formed monolithically with the first jaw body as a single
piece. The device also includes a second jaw having a second jaw body
having a proximal portion and a distal clamping portion, and a second
bearing surface formed monolithically with the second jaw body. The
second jaw is rotatably coupleable to the first jaw such that the first
bearing surface communicates with the second bearing surface at an
interface. The device also includes a driver configured to rotate the
first jaw with respect to the second jaw with the interface acting as a
fulcrum and defining an axis of rotation between the first jaw and the
second jaw.

[0026] The first bearing surface and the second bearing surface may be
configured to slide with respect to each other along the interface when
the driver rotates the first jaw with respect to the second jaw.

[0027] The interface may extend along a circular arc, the first jaw
rotatable with respect to the second jaw about an axis of rotation
corresponding to the circle center of the circular arc.

[0028] The first bearing surface may be formed in the first jaw without
extending entirely through the first jaw and the second bearing surface
may be formed in the second jaw without extending entirely through the
second jaw.

[0029] The first jaw may include a first wing and a second wing, the first
wing including a first blind slot and the second wing including a second
blind slot.

[0030] The driver may include a shaft configured to extend into each of
the first blind slot and the second blind slot.

[0031] The shaft may be actuatable along a slot in the second jaw to
rotate the first jaw with respect to the second jaw.

[0032] The shaft may be disposed proximally with respect to the interface
between the first bearing surface and the second bearing surface.

[0033] The first jaw may be axially insertable and removable from the
second jaw when no clamping force is applied between the first jaw and
the second jaw.

[0034] The device may further include a secondary positioning member
coupled to one of the first jaw and the second jaw and configured to
prevent axial removal of the first jaw from the second jaw and to permit
rotation of the first jaw with respect to the second jaw.

[0035] The secondary positioning member may be configured to limit the
range of rotation between the first jaw and the second jaw to a
predetermined angular range.

[0036] The secondary positioning member may be configured to extend from
the one of the first jaw and the second jaw into a curved slot of the
other one of the first jaw and the second jaw.

[0037] The curved slot may be a blind slot.

[0038] Further details and aspects of example embodiments of the present
invention are described in more detail below with reference to the
appended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIGS. 1a and 1b show a clamping device according to an example
embodiment of the present invention.

[0057] FIGS. 1a and 1b show a clamping device 10 of a linear cutting and
stapling device according to an example embodiment of the present
invention. The clamping device 10 includes an anvil 100 as a first jaw or
clamping member, and a cartridge housing 200 as a second jaw clamping
member. As shown in FIGS. 1a and 1b, the anvil 100 and the cartridge
housing 200 are in an open state. The anvil 100 and cartridge housing 200
are rotatable about each other to close from the open state to a closed
state where the anvil 100 and cartridge housing 200 are parallel, or
substantially parallel, to maintain a tissue gap therebetween that allows
for satisfactory staple formation between the cartridge housing 200 and
the anvil 100.

[0058] It is noted that the clamping device 10 is symmetric, or
substantially symmetric, about a plane extending through an axial
centerline of the clamping device 10. Thus, although some features may be
described with respect to one side of the clamping device, it should be
understood than analogous features are disposed on the opposite side of
the clamping device. It should be further understood that, although the
clamping device 10 is symmetric, or substantially symmetric, other
example embodiments may not be.

[0059] FIG. 2 is an exploded view of the clamping device 10 of FIGS. 1a
and 1b. The clamping device 10 includes a guide screw or member 20, an
inner shaft 30, a clamp screw 40, a firing shaft 50, a bevel gear shaft
60, a proximal housing 70, and screws 80.

[0060] Referring to FIGS. 3 and 4, the guide member 20 is coupled to the
proximal housing 70 and rotatably receives the clamp screw 40. Further
referring to FIGS. 5a and 5b (FIG. 5a is a cross section taken through a
plane crossing the mid- or centerline of the clamping device 10, while
the cross-sectional view of FIG. 5b is taken through a plane that is
slightly offset from the centerline of the clamping device 10), the guide
member 20 has a flange 21 that contacts the staple cartridge housing 200
to prevent the flange from moving axially in a distal direction. A
proximal face of the flange 21 contacts the proximal housing to restrain
the guide member from moving proximally.

[0061] The clamp screw 40 has a head or proximal portion 41 configured to
receive a driver to axially rotate the clamp screw 40. The clamp screw 40
also has an externally threaded shaft 42 that engages corresponding
internal threads of the inner shaft 30. In this regard, axial rotation of
the clamp screw 40 in a first direction causes the external threads to
rotate within the inner shaft 30 to cause the inner shaft 30 to move in a
proximal direction. As set forth in greater detail below, this proximal
movement is translated into a clamping force applied between the anvil
100 and the cartridge housing 200. To facilitate rotation of the clamp
screw 40 during the clamping, a thrust bearing 22 is provided to transmit
the axial force between the clamp screw 40 and the guide member 20 about
the guide member 20. Rotation of the clamp screw 40 in a second, opposite
direction causes the inner shaft 30 to move distally, causing the anvil
100 to rotate away from the cartridge housing. A distal end portion of
the clamp screw 40 is received in a bore 202 of the cartridge housing 200
to constrain the distal end of the clamp screw 40 during clamping.

[0062] To drive a cutting and stapling function, the clamping device 10
includes a firing shaft 50 and a bevel gear shaft 60. The bevel gear
shaft 60 is coupled to the firing shaft 50 such that rotation of the
bevel gear shaft causes rotation of the firing shaft 50. This rotation of
the firing shaft is then used to drive a cutting and staple-pushing
element in a distal direction to cut and staple clamped tissue. The
staples are driven from a staple cartridge received by the cartridge
housing 200.

[0063] Referring to FIG. 5b and FIG. 13, which is a cross sectional view
taken through an interface 300 between the anvil 100 and the cartridge
housing 200, the anvil 100 is rotatably coupled to the cartridge housing
200 at the interface 300. The interface 300 is formed between a concave
surface 210 of the cartridge housing 200 and a convex surface 110 of the
anvil 100. The concave surface 210 of the cartridge housing 200 is shown,
e.g., in FIGS. 10 to 12, and the convex surface 110 of the anvil 100 is
shown, e.g., in FIGS. 6 to 9.

[0064] The convex surface 110 of the anvil 100 corresponds to the profile
of a raised portion or protrusion 115 that extends or projects away from
a lateral surface or face 120 to a raised surface or face 125. Although
the protrusion 115 extends inwardly (i.e., in a direction toward an axial
centerline of the anvil 100) from an inwardly facing surface 120 (i.e., a
surface facing laterally toward the centerline of the anvil 100), it
should be understood that the protrusion 115 may extend away from an
outwardly facing surface and/or the protrusion 115 may extend between two
opposed surfaces.

[0065] The concave surface 210 of the cartridge housing 200 corresponds to
the profile of an undercut or inset into a lateral surface or face 220.
Although the inset is formed to extend inwardly from an outwardly facing
surface 220, it should be understood that the inset may be formed to
extend outwardly into an inwardly facing surface and/or the inset may
extend through the material to an opposite face or surface.

[0066] Further, the concave surface 210 is formed at a step between the
face 220 and an inset surface or face 225. The surface 225 is formed on
the lateral side of a support member or rib 230. In the example
embodiment, the rib 230 separates the concave surface 210 and the inset
from a symmetrically formed, or substantially symmetrically formed,
second concave surface and second inset. This second structure is formed
as "mirror image" such that the structure is symmetric about a plane that
intersects the axial centerline of the cartridge housing 200 and
corresponds to a plane in which the anvil 100 is rotatable with respect
to the cartridge housing 200 when the anvil 100 is mated to the cartridge
housing 200 at the interface 300. It should be appreciated, however, that
the support member 230 may be dispensed with, such that, e.g., the
concave surface 210 extends laterally across the cartridge housing 200 to
form a single surface 210. The support member 230 may be advantageous,
however, in that it may help prevent deformation of the cartridge housing
200 due to high forces being exerted at the interface 300.

[0067] When the anvil 100 and the cartridge housing 200 are mated, the
convex surface 110 is slidably coupled with the concave surface 210. The
contact surface between the convex surface 110 forms an arc with a center
corresponding to an axis of rotation between the anvil 100 and the
cartridge housing 200. In this regard, the radius of curvature of the
concave surface 210 and the convex surface 110 are the same, or
substantially the same. This may ensure accurate positioning of anvil 100
with respect to the cartridge housing 200, as well as providing a
constant, or substantially constant, axis of rotation between the anvil
100 and the cartridge housing 200 during clamping.

[0068] Although the interface 300 provides a sliding interface, it should
be understood that other configurations may be provided. For example a
rolling interface may be provided. For example, the concave surface 210
may have a larger radius of curvature than the convex surface 110. Where,
e.g., such a rolling arrangement is provided, the concave surface 210 and
the convex surface 110 may be provided with mating teeth, e.g., gear
teeth, which may be formed with the respective anvil 100 and cartridge
housing 200 monolithically.

[0069] Although the clamping device 10 has two mating interfaces 300 it
should be understood that the clamping device 10 may have multiple mating
interfaces 300 and that one of the anvil 100 and the cartridge housing
200 may have a combination of convex and concave geometries that mate
with a corresponding combination of concave and convex geometries on the
other of the anvil 100 and the cartridge housing 200.

[0070] Due to the geometry of the interface 300, the anvil 100 is
constrained axially with respect to the cartridge housing 200 when the
convex surface 110 is pressed into the concave surface, e.g., during
clamping. In this regard, the contact or interface surface 300 extends
from a point proximal to the rotation axis, or center of curvature of the
arc of interface 300 (which corresponds to the center of curvature of the
convex surface 110 and the center of curvature of the concave surface
210) to a point proximal to the center of the arc of curvature of the
interface 300. Thus, the surface 210 of the cartridge housing 200 is able
to exert forces (normal to the surface 210) that have proximally directed
components and distally directed components, thereby accurately
maintaining the axial position of the anvil 100 with respect to the
cartridge housing 200.

[0071] It should be appreciated that, although the interface 300 includes
a single contact or interface surface, the interface may be provided with
multiple and/or intermittent contact or interface surfaces.

[0072] When the convex surface 110 is not pressed into the concave surface
210, e.g., when no clamping force is applied to the anvil 100, the
surface 110 may separate from the surface 210, in which case the anvil
100 may be moved axially with respect to the cartridge housing 200 such
that the surface 110 clears the surface 210. In this manner, the anvil
100 may be removed, or decoupled, from the cartridge housing 200.

[0073] When it is not desired to remove the anvil 100 from the cartridge
housing 200, in the absence of a load being applied to the anvil 100, or
when the mated surfaces 110, 120 are not being pressed together, the
position of the anvil 100 is maintained by one or more secondary
positioning members 80. The secondary positioning members 80 of the
device 10 are shown as, e.g., screws. Each secondary positioning member
80 is supported by the cartridge housing 200 and extends into a secondary
positioning slot 140 in the anvil 100. The secondary positioning slot 140
has an arced geometry, the center of curvature of the arc located at the
axis of rotation of the anvil 100 with respect to the cartridge housing
when the surfaces 110 and 210 are mated. Thus, the extension of the
secondary positioning member into the secondary positioning slot 140 does
not interfere with the rotational motion of the anvil 100 with respect to
the cartridge housing 200 when the anvil 100 is moved between an open
position and a closed position. The length and/or positioning of the
arced slot may be selected, however, to limit the range of rotation of
the anvil 100 when rotated about the cartridge housing. This limiting
would be provided due to contact or interference between the secondary
positioning member 80 and one or both of the ends of the arced secondary
positioning slot 140.

[0074] The secondary positioning member 80 is a screw having external
threads that engage internal threads of a secondary positioning aperture
240 of the cartridge housing 200.

[0075] Although the secondary positioning member 80 is a screw, it should
be appreciated that the secondary positioning member 80 may be any
appropriate structure, e.g., a pin. Moreover, although the slot 140 is a
blind slot (i.e., the depth of the slot does not extend entirely through
the structure of the anvil 100), a through slot may be provided. A blind
slot may be advantageous, however, due to the added rigidity provided by
the material at the bottom of the slot. It should be further appreciated
that the secondary positioning member 80 may be supported in either of
the anvil 100 and the cartridge housing 200. Further, although two
secondary positioning members 80 are shown, more than two secondary
positioning members 80 may be provided, or a single secondary positioning
member 80 may be provided. For example, a single pin or screw could
extend through both slots 140.

[0076] Referring to FIGS. 5a to 5c, to actuate the rotation of the anvil
100, the inner shaft 30 moves proximally and distally within a slot 205
of the cartridge housing 200. The slot 205 constrains the inner shaft 30
to an axial path with respect to the cartridge housing 200. Thus, the
inner shaft 30 may move distally and proximally along this path, but is
limited with regard to movement in other directions in the plane of
rotation of the anvil 100 about the cartridge housing 200. It should be
appreciated that the path of the inner shaft 30 provided by the slot 205
need not necessarily be linear. The cartridge housing 200 may also
rotationally constrain the inner shaft 30 about the axis of the clamp
screw 40 with respect to the cartridge housing 200 such that rotation of
the clamp screw 40 with respect to the cartridge housing 200 does not
cause rotation of the inner shaft 30 about the cartridge housing 200.
Thus, clamp screw 40 rotates relative to the cartridge housing 200 and
the inner shaft 30, the threaded engagement between the clamp screw 40
and the inner shaft 30 causing the inner shaft 30 to translate distally
or proximally depending on the direction of rotation of the clamp screw
40.

[0077] The inner shaft 30 extends laterally outwardly into actuation slots
105 of the anvil 100, such that the distal or proximal translation of the
inner shaft 30 within the slot 205 of the cartridge housing 200 causes
the shaft to translate, e.g., slide, along the paths of the actuation
slots 105. It should be appreciated that the inner shaft 30 may be
configured to roll along the slots 105 of the anvil 100 and/or along the
slot 205 of the cartridge housing 200.

[0078] Each slot 105 is located and oriented such that the movement of the
inner shaft 30 along the slot 205 of the cartridge housing 200 and along
the actuation slot 105 of the anvil 100 causes the anvil 100 to rotate
with respect to cartridge housing 200. This is accomplished by providing
the slots 105 and 205 such that the distal portions of the slots 105 and
205 align when the anvil 100 is in the open position with respect to the
cartridge housing 200 and the proximal portions of the slots 105 and 205
align when the anvil 100 is in a closed position with respect to the
cartridge housing 200. In this regard, the inner shaft 30 serves to align
the slots 105 and 205 at the position along the slots 105 and 205 at
which the inner shaft 30 is located. Thus, when the clamp screw 40
rotates in a first direction to translate the inner shaft 30 in the
proximal direction, the alignment location of the slots 105 and 205 moves
proximally, thereby moving the anvil 100 toward the closed position with
respect to the cartridge housing 200, and vice-versa when the clamp screw
40 is rotated in the opposite direction.

[0079] During clamping, the interaction between the inner shaft 30 and the
slots 105 and 205 acts to press the proximal portions of the anvil 100
and the cartridge housing 200 away from each other. In this regard, the
interface 300 between the convex surface 110 of the anvil 100 and the
concave surface 210 of the cartridge housing 200 acts a fulcrum such that
the distal clamping portions of the anvil 100 and the cartridge housing
200 are urged together.

[0080] Although the slots of the example clamping device 10 are positioned
proximal to the axis of rotation of the anvil 100 with respect to the
cartridge housing 200, it should be appreciated that the slots 105 and
205 may be position distal to the axis of rotation. In this situation,
the interaction between the inner shaft and the slots would act to pull
the anvil 100 toward the cartridge housing 200 at a location between the
axis of rotation and the distal clamping portions of the anvil 100 and
the cartridge housing 200.

[0081] The proximal ends of the actuation slots 105 of the anvil 100 are
open. This allows the anvil 100 to be coupled and decoupled to and from
the cartridge housing 200 in a simple and expeditious manner. To couple
the anvil 100 to the cartridge housing 200, the open ends of the
actuation slots 105 are aligned to receive the lateral extensions of the
inner shaft 30. The anvil 100 is moved proximally so that the slots
receive and slide along the axial extensions of the inner shaft 30 until
the convex surface 110 of the anvil 100 is positioned below the concave
surface 210 of the cartridge housing 200. The secondary positioning
members 80 may then be inserted to extend into the secondary positioning
slots 140.

[0082] To remove the anvil 100, the secondary positioning members 80 may
be retracted and/or removed. The anvil 100 may then be pulled distally,
allowing the convex surface 110 to clear the concave surface 210, until
the lateral extensions of the inner shaft 30 exit the open proximal ends
of the actuation slots 105.

[0083] As shown, e.g., in FIGS. 6 to 9, the proximal portion of the anvil
100 has two parallel, or substantially parallel, extensions or wings 150
into which the slots 205 are formed. The extensions 150 are separated by
a medial space 160 that extends distally to a point beyond the convex
surfaces 110. The protrusions 115 (along with convex surfaces 110) and
the actuation slots 105 are formed or disposed on the medial or inner
sides or faces of the extensions 150, while the secondary positioning
slots 140 are formed or disposed on the outer sides or faces of the
extensions 150.

[0084] The strength of the extensions 150 benefits from the presence of
outer structure 151 adjacent to the blind slots 105, as opposed to
through slots that would not have this structure 151. The strengthening
due to this structure 151 may reduce the possibility of deflection and/or
deformation of the extensions 150 under high clamping loads.

[0085] When the anvil 100 is coupled to the cartridge housing 200 as
described above, the extensions 150 are received in a pair of channels
260 of the cartridge housing 200, as shown, e.g., in FIG. 14. Thus, the
extensions 150 of the anvil 100 are generally laterally captivated,
confined or constrained in a particular arrangement by the cartridge
housing 200. The channels 260 separate a middle extension 270 and two
outer extensions 280. The middle extension 270 includes the slot 205, and
the concave surfaces 210, while the outer extensions 280 include the
secondary positioning apertures 240. The middle extension 270 also
includes first and second axial apertures 290 and 291, which extend
axially, referring to FIG. 5a, through the middle extension 270 to
corresponding proximal openings in the middle extension 270. The first
axial aperture 290 allows the firing shaft 50, which is housed in an
enclosed channel or bore 292 of the middle extension 270, to access and
drive a cutting and staple-driving element in the distal portion of the
cartridge housing 200. The second aperture 291 provides access to an
enclosed channel or bore 293 between the distal and proximal ends of the
middle extension 270. The channel 293 may be used for any appropriate
purpose, including, e.g., providing a housing for wiring, which may be
used, e.g., to communicate information related to staple cartridges that
may be housed in the cartridge housing 200. The information may be, e.g.,
stored on a chip of the staple cartridge. The distal portion of the
cartridge housing 200, which functions as a lower clamping jaw, includes
a channel 275 configured to receive the staple cartridge.

[0086] The lateral confinement, captivation or constraint of the
extensions 160 of the anvil 100 may serve to prevent or reduce the
likelihood of lateral deflection and/or deformation of the extensions
160, e.g., under high clamping forces.

[0087] Further, the structure of the extensions 270 and 280 of the
cartridge housing 200 may prevent or reduce the likelihood of deflection
and/or deformation of the cartridge housing 200. In this regard, the
extensions 270 and 280 extend in the plane of the clamping rotation of
the anvil with respect to the cartridge housing. This may provide added
strength in the plane of the clamping rotation of the anvil 100 with
respect to the cartridge housing 200. Further, the presence of
substantial structure due to the outer extensions 280 at a distance
(e.g., along the lateral circumference of the cartridge housing 200) from
the axial centerline of the cartridge housing 200 may provide increased
torsional rigidity to further resist deflection of the cartridge housing
200.

[0088] The cartridge housing 200 includes lateral supports or ribs 271,
272 that extend between the middle extension 270 and the outer extensions
280. The lateral supports 271, 272 are spaced and dimensioned to avoid
interfering with the rotation of the wings or extensions 150 of the anvil
100 when the anvil 100 is rotated during clamping and opening procedures.

[0089]FIG. 15 illustrates an alternative clamping device 1000. The device
1000 includes a first jaw or anvil 1100 and a second jaw or staple
cartridge housing 1200. The staple cartridge housing 1200 is shown with a
staple cartridge 1600, which is of a type also insertable into the staple
cartridge housing 200 described above. The anvil 1100 is rotatable with
respect to the cartridge housing 1200 about a pin inserted through a bore
1103 of the anvil 1100 and a corresponding bore of the cartridge housing
1200. The anvil 1100 is actuatable between an open state and a closed
state via actuation of a shaft 1030 along a slot 1205 of the cartridge
housing 1200 and a pair of slots 1105 of the anvil.

[0090] The slots 1105 are formed in two respective wings or extensions
1150 of the anvil 1100. As opposed to the slots 105 disposed in the
extensions 150 of the anvil 100, the slots 1105 are through-slots,
extending entirely through the structure of each respective extension
1150. Thus, under high clamping forces applied between the anvil 1100 and
the cartridge housing 1200, the extensions 1150 may be more likely to
deflect and/or deform. Moreover, the bore 1103, which forms a through
hole in the anvil 1100, may further reduce the clamping forces that may
be applied without deflection or deformation in the anvil 1100 and/or the
cartridge housing 1200, as opposed to the interface 300 of the clamping
device 10.

[0091] Further, the clamping device 1000 does not include any structure
disposed laterally (along the axis of rotation) outside of the extensions
1150. Thus, under high clamping forces, the extensions 1150 have less
constraint against laterally outward deflection, as compared to the
clamping device 10, where the outer extensions 280 of the cartridge
housing 200 extend along laterally outward sides of the extensions 150 of
the anvil 100 to generally laterally confine in a particular arrangement
the extensions 150.

[0092] Still further, since the only structure of the cartridge housing
1200 extending along the axial extension of the slot 1205 is a single
vertically oriented axial extension 1208, the cartridge housing 1200 may
be more susceptible to deflection, as opposed to the cartridge housing
200, which has the additional structural support provided by the two
outer extensions 280. With regard to the clamping device 1000, it is
noted that the stresses due to the clamping forces exerted between the
distal portions of the anvil 1100 and the cartridge housing 1200 are
concentrated in the interface between the distal or jaw portion and the
single extension 1208. In contrast, referring to the clamping device 10
illustrated, e.g., in FIGS. 11 and 12, the interface between the distal
or jaw portion of the cartridge housing 200 is spread among the two outer
extensions 280 and the middle extension 270. This may allow greater
clamping forces to be applied without unacceptable deflection or fatigue
failure at the junction between the distal jaw portion and the proximal
portion of the cartridge housing 200.

[0093] FIG. 16 shows a surgical instrument 5 including the clamping device
10. The clamping device 10 is coupled to a shaft housing 11, that
contains a first drive shaft configured to drive clamp screw 40 and a
second drive shaft configured to drive bevel gear shaft 60. At a proximal
end of the shaft housing 11 is a handle portion 12 that includes user
controls and at least one actuator configured to rotate the first and
second drive shafts based on the user controls. In this regard, the drive
shafts are independently rotatable so that the clamping (or opening) of
the jaws may be controlled independently from the driving of the
cutter/staple pusher. The instrument contains many features that are
analogous to the instruments described in U.S. Patent Application
Publication No. 2009/0101692, which is expressly incorporated herein in
its entirely by reference thereto. Although the example instrument 5 is a
hand-held, self-contained, battery-powered unit, it should be appreciated
that the clamping device 10 may be provided with any appropriate
instrument, e.g., a console-based surgical instrument.

[0094] FIGS. 17 and 18 show a clamping device 2000. The clamping device
2000 includes the features of the clamping devices described above, but
differs in that the anvil 2100 includes through slots 2105 rather than
blind slots 105. This arrangement may be suitable to simplify the
manufacturing of the slots.

[0095] Since the through slots 2105 do not have open proximal ends, such
as those of blind slots 105, the clamping device is not assembled in
exactly the same manner as described above with regard to clamping device
10. This is because the closed distal end of the through slots 2105
prevent the anvil 2100 from being proximally slid onto the inner shaft
2030. Thus, the anvil 2100 is rotatably coupled to the housing 2200 prior
to placement of the inner shaft 2030. In this regard, after the anvil
2100 is coupled to the housing 2200, the through slot 2105 of the anvil
2100 is aligned with a hole or aperture 2400 in the side of the housing
2200. At this stage, the inner shaft 2030 may be inserted through the
hole 2400 until the inner shaft 2030 engages both through slots 2105. The
clamp screw 2040 may then by inserted to engage the inner threads of the
inner shaft 2030.

[0096] To reduce any possibility of contamination, e.g., dirt, entering
the mechanism through the hole 2400, a plug 2500 is provided, which
closes the hole after the inner shaft 2030 has been inserted
therethrough. Although the clamping device 2000 has a single hole with a
single plug, it should be understood that two or more holes and/or two or
more plugs may be provided. However, it may be suitable to minimized the
number of holes to limit the possibility of contamination, simplify the
manufacturing process, and/or reduce any possibility of compromising the
strength of the housing 2200.

[0097] Although the through slots 2105 are shown as enclosed, it should be
understood that the through slots 2105 may have a forked structure, such
that one end of one or more of the slots 2105, e.g., a proximal end, is
open.

[0098] Although the present invention has been described with reference to
particular examples and exemplary embodiments, it should be understood
that the foregoing description is in no manner limiting. Moreover, the
features described herein may be used in any combination.